Analysis of reciprocal lossy periodic transmission-line structures using bi-characteristic-impedance transmission lines and Meta-Smith charts

2015 ◽  
Author(s):  
Suthasinee Lamultree ◽  
Danai Torrungrueng ◽  
Prayoot Akkaraekthalin
Keyword(s):  
Transmission Line ◽  
Transmission Lines ◽  
Characteristic Impedance ◽  
Periodic Transmission

Transmission Line

2020 ◽  
pp. 43-71
Keyword(s):  
Transmission Line ◽  
Transmission Lines ◽  
Magnetic Energy ◽  
Propagation Constant ◽  
Characteristic Impedance ◽  
Electric Energy ◽  
Electromagnetic Energy ◽  
The Other ◽  
Electrical Characteristics ◽  
Lumped Elements

A transmission line (TL) is simply a medium that is capable of guiding or propagating electromagnetic energy. The transmission line stores the electric (E) and magnetic (M) energies and distributes them in space by alternating them between the two forms. This means that at any point along a TL, energy is stored in a mixture of E and M forms and, for an alternating signal at any point on the TL, converted from one form to the other as time progresses. Transmission line is usually modelled using lumped elements (i.e., inductors for magnetic energy, capacitors for electric energy, and resistors for modelling losses). The electrical characteristics of a TL such as the propagation constant, the attenuation constant, the characteristic impedance, and the distributed circuit parameters can only be determined from the knowledge of the fields surrounding the transmission line. This chapter gives a brief overview of various transmission lines, with more detailed discussions on the microstrip and the SIW.

scholarly journals Solving the Complexity Problem in the Electronics Production Process by Reducing the Sensitivity of Transmission Line Characteristics to Their Parameter Variations

Complexity ◽  
2019 ◽  
Vol 2019 ◽  
pp. 1-11 ◽  
Author(s):  
Talgat R. Gazizov ◽  
Indira Ye. Sagiyeva ◽  
Sergey P. Kuksenko
Keyword(s):  
Transmission Line ◽  
Production Process ◽  
Transmission Lines ◽  
Unit Length ◽  
Characteristic Impedance ◽  
Optimal Choice ◽  
Wide Range ◽  
Complexity Problem ◽  
Parameter Variations ◽  
Parameter Values

In this paper we consider the complexity problem in electronics production process. Particularly, we investigate the ways to reduce sensitivity of transmission line characteristics to their parameter variations. The reduction is shown for the per-unit-length delay and characteristic impedance of several modifications of microstrip transmission lines. It can be obtained by means of making an optimal choice of parameter values, enabling proper electric field redistribution in the air and the substrate. To achieve this aim we used an effective simulation technique and software tools. Taken together, for the first time, they have allowed formulating general approach which is relevant to solve a wide range of similar tasks.

scholarly journals Applying the Retarded Solutions of Electromagnetic Fields to Transmission Line RLGC Modeling

2017 ◽  
Vol 6 (1) ◽  
pp. 56
Author(s):  
P. Ye ◽  
B. Gore ◽  
P. Huray
Keyword(s):  
Transmission Line ◽  
Transmission Lines ◽  
Analytical Approach ◽  
Propagation Constant ◽  
Unit Length ◽  
Characteristic Impedance ◽  
Simulation Methods ◽  
Arbitrary Length ◽  
Small Segment ◽  
Numerical Simulation Methods

The RLGC model, and its variations, is one of the most common techniques to simulate Transmission Lines. The RLGC model uses circuit network elements consisting of Resistance R, Inductance L, Conductance G and Capacitance C (per unit length) to represent a small segment of the Transmission Line, and then cascades multiple segments to simulate the Transmission Line of arbitrary length. Typically the parameters in RLGC model are extracted from the propagation constant and characteristic impedance of the transmission line, which are found using numerical simulation methods. These resulting RLGC parameters for multi-GHz signaling are usually frequency-dependent. This paper introduces an analytical approach to extract RLGC parameters to simulate transmission line, which results in a different model, the RLGC(p) model.

scholarly journals Highly Sensitive Reflective-Mode Defect Detectors and Dielectric Constant Sensors Based on Open-Ended Stepped-Impedance Transmission Lines

Sensors ◽  
2020 ◽  
Vol 20 (21) ◽  
pp. 6236
Author(s):  
Pau Casacuberta ◽  
Jonathan Muñoz-Enano ◽  
Paris Vélez ◽  
Lijuan Su ◽  
Marta Gil ◽  
...  
Keyword(s):  
Dielectric Constant ◽  
Transmission Line ◽  
Transmission Lines ◽  
Characteristic Impedance ◽  
Reference Sample ◽  
Phase Variation ◽  
Dielectric Constants ◽  
High Impedance ◽  
Line Section ◽  
Highly Sensitive

In this paper, reflective-mode phase-variation sensors based on open-ended stepped-impedance transmission lines with optimized sensitivity for their use as defect detectors and dielectric constant sensors are reported. The sensitive part of the sensors consists of either a 90° high-impedance or a 180° low-impedance open-ended sensing line. To optimize the sensitivity, such a sensing line is cascaded to a 90° transmission line section with either low or high characteristic impedance, resulting in a stepped-impedance transmission line configuration. For validation purposes, two different sensors are designed and fabricated. One of the sensors is implemented by means of a 90° high impedance (85 Ω) open-ended sensing line cascaded to a 90° low impedance (15 Ω) transmission line section. The other sensor consists of a 180° 15-Ω open-ended sensing line cascaded to a 90° 85-Ω line. Sensitivity optimization for the measurement of dielectric constants in the vicinity of that corresponding to the Rogers RO4003C substrate (i.e., with dielectric constant 3.55) is carried out. The functionality as a defect detector is demonstrated by measuring the phase-variation in samples consisting of the uncoated Rogers RO4003C substrate (the reference sample) with arrays of holes of different densities.

scholarly journals Matching the termination of radiating non-uniform transmission-lines

2013 ◽  
Vol 11 ◽  
pp. 259-264 ◽  
Author(s):  
R. Rambousky ◽  
J. Nitsch ◽  
H. Garbe
Keyword(s):  
Transmission Line ◽  
Transmission Lines ◽  
Characteristic Impedance ◽  
Local Effect ◽  
Single Wire ◽  
Concentrated Load ◽  
Frequency Dependent ◽  
Radiated Power ◽  
Maximum Value ◽  
Cooperative Process

Abstract. In this contribution a concept of matching the termination of radiating non-uniform transmission-lines is proposed. Using Transmission-Line Super Theory, position and frequency dependent line parameters can be obtained. Therefore, a characteristic impedance can be determined which is also position and frequency dependent. For a single wire transmission-line it could be shown that the maximum value of that characteristic impedance is an optimal termination in the sense of minimizing the variation of the current on the line. This indicates that matching is not a local effect at the position of the concentrated load but a cooperative process including the whole non-uniform transmission-line. In addition this choice of termination minimizes the variation of the radiated power over frequency.

Transmission lines characteristic impedance versus Q-factor in CMOS technology

2021 ◽  
pp. 1-6
Author(s):  
Johannes J.P. Venter ◽  
Anne-Laure Franc ◽  
Tinus Stander ◽  
Philippe Ferrari
Keyword(s):  
Transmission Line ◽  
Slow Wave ◽  
Transmission Lines ◽  
Characteristic Impedance ◽  
Ground Plane ◽  
Cmos Technology ◽  
Wave Transmission ◽  
60 Ghz ◽  
Q Factor ◽  
Chip Area

Abstract This paper presents a systematic comparison of the relationship between transmission line characteristic impedance and Q-factor of CPW, slow-wave CPW, microstrip, and slow-wave microstrip in the same CMOS back-end-of-line process. It is found that the characteristic impedance for optimal Q-factor depends on the ground-to-ground spacing of the slow-wave transmission line. Although the media are shown to be similar from a mode of propagation point of view, the 60-GHz optimal Q-factor for slow-wave transmission lines is achieved when the characteristic impedance is ≈23 Ω for slow-wave CPWs and ≈43 Ω for slow-wave microstrip lines, with Q-factor increasing for wider ground plane gaps. Moreover, it is shown that slow-wave CPW is found to have a 12% higher optimal Q-factor than slow-wave microstrip for a similar chip area. The data presented here may be used in selecting Z0 values for S-MS and S-CPW passives in CMOS that maximize transmission line Q-factors.

scholarly journals Modeling and Analysis of Sub-Millimeter-Wave Graphene Switches for On-Wafer Coplanar Transmission Lines

2020 ◽  
Author(s):  
Panagiotis Theofanopoulos ◽  
Georgios Trichopoulos
Keyword(s):  
Transmission Line ◽  
Transmission Lines ◽  
Characteristic Impedance ◽  
Design Parameters ◽  
Coplanar Waveguides ◽  
Modeling And Analysis ◽  
Switching Performance ◽  
Line Characteristic ◽  
Depth Study ◽  
Impedance Scaling

We present an analysis of graphene loaded transmission line switches. Namely, we propose equivalent circuit models for graphene loaded coplanar waveguides and striplines and examine the switching performance under certain design parameters. As such, the models account for the distributed effects of electrically-large shunt switches in coplanar waveguides and we use the Babinet’s principle to derive the respective models for the coplanar stripline transmission lines. Using these models, we identify the optimum design of graphene switches based on transmission line characteristic impedance, scaling factor, graphene shape, and topology (series or shunt). We vary these parameters and obtain the insertion loss and ON/OFF ratio. Τhe extracted results can act as the design roadmap toward an optimum switch topology and emphasize the limitations with respect to fabrication challenges, parasitic effects, and radiation losses. In our models, we use measured graphene values (sheet impedance) instead of theoretical equations, to obtain the actual switching performance. Finally, the proposed equivalent models are crucial for this in-depth study; since, we simulated more than 2,000,000 configurations, a computationally challenging task with the use of full-wave solvers

scholarly journals Compact Two-Section Half-Wave Balun Based on Planar Artificial Transmission Lines

2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Changjun Liu ◽  
Zhenyu Yin ◽  
Yilan Yang ◽  
Wen Huang
Keyword(s):  
Transmission Line ◽  
Transmission Lines ◽  
Microwave Power ◽  
Parallel Plate ◽  
Return Loss ◽  
Characteristic Impedance ◽  
Size Reduction ◽  
Power Combining ◽  
Half Wave ◽  
Phase Balance

Artificial transmission lines are realized by a series of meandered-line inductors, parallel-plate capacitors, and interdigital capacitors, which belong to metamaterial transmission lines. An ameliorated artificial transmission line is proposed to realize a low characteristic impedance transmission line. A two-section half-wave balun at 900 MHz is designed, fabricated, and measured in this paper. The compact balun is based on conventional and ameliorated planar artificial transmission lines instead of microstrip transmission lines. The main advantage of the proposed balun is its size reduction, which occupies only about 10% of a conventional one. Measured results match well with theory and simulation. The balun features excellent amplitude and phase balance in microwave power combining and a reasonable bandwidth of the return loss as well.

scholarly journals Moving Reference Planes of Unit Cells of Reciprocal Lossy Periodic Transmission-Line Structures

2018 ◽  
Vol 16 (2) ◽  
pp. 15-20
Author(s):  
Suthasinee Lamultree
Keyword(s):  
Transmission Line ◽  
Propagation Constant ◽  
Characteristic Impedance ◽  
Numerical Results ◽  
Reflection Coefficients ◽  
Bilinear Transformation ◽  
Reference Position ◽  
Unit Cells ◽  
Complex Propagation ◽  
Periodic Transmission

An analysis of moving reference planes of unit cells of reciprocal lossy periodic transmission-line (TL) structures (RLSPTLSs) by using the equivalent bi- characteristic-impedance transmission line (BCITL) model is presented. Applying the BCITL theory, only the equivalent BCITL parameters (characteristic impedances for wave propagating in forward and reverse directions and associated complex propagation constant) are of interest. In the analysis, an arbitrary infinite RLSPTLS is firstly considered by shifting a reference position of unit cells along TLs. Then, a semi-infinite terminated RLSPTLS is subsequently investigated in term of associated load reflection coefficients. It is found that the equivalent BCITL characteristic impedances of the original and shifted unit cells, as well as the associated load reflection coefficients of both unit cells, are mathematically related by the bilinear transformation. However, the equivalent BCITL complex propagation constant remains unchanged. Numerical results are provided to show the validity of the proposed technique.

scholarly journals Modeling and Analysis of Sub-Millimeter-Wave Graphene Switches for On-Wafer Coplanar Transmission Lines

2020 ◽  
Author(s):  
Panagiotis Theofanopoulos ◽  
Georgios Trichopoulos
Keyword(s):  
Transmission Line ◽  
Transmission Lines ◽  
Characteristic Impedance ◽  
Design Parameters ◽  
Coplanar Waveguides ◽  
Modeling And Analysis ◽  
Switching Performance ◽  
Line Characteristic ◽  
Depth Study ◽  
Impedance Scaling

We present an analysis of graphene loaded transmission line switches. Namely, we propose equivalent circuit models for graphene loaded coplanar waveguides and striplines and examine the switching performance under certain design parameters. As such, the models account for the distributed effects of electrically-large shunt switches in coplanar waveguides and we use the Babinet’s principle to derive the respective models for the coplanar stripline transmission lines. Using these models, we identify the optimum design of graphene switches based on transmission line characteristic impedance, scaling factor, graphene shape, and topology (series or shunt). We vary these parameters and obtain the insertion loss and ON/OFF ratio. Τhe extracted results can act as the design roadmap toward an optimum switch topology and emphasize the limitations with respect to fabrication challenges, parasitic effects, and radiation losses. In our models, we use measured graphene values (sheet impedance) instead of theoretical equations, to obtain the actual switching performance. Finally, the proposed equivalent models are crucial for this in-depth study; since, we simulated more than 2,000,000 configurations, a computationally challenging task with the use of full-wave solvers

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